Bulk material conveyor apparatus constructions utilizing flexible endless material-moving belts, formed U-shaped troughs that frictionally support conveyor system endless belts, and drive, idle, and tensioning roll endless belt drives, in combination, are well known. Also, en masse bulk material conveyor apparatus construction utilizing spaced frames or skeletonized flights attached to an endless cable or chain are well known. An en masse conveyor is a machine in which the material moves within a stationary duct as a continuous core as contrasted with the manner of movement of material conveyed by a screw or flight conveyor, bucket elevator or belt conveyor. Achieving "en masse" movement depends upon the material moved having a higher internal friction factor than the materials friction factor on the contact surface on the stationary trough. Conveyors based on this principal have the advantage of conveying large capacity relative to their cross section. Traditional en masse conveyors utilize chain and flights to effect en masse movement but are limited as to length and speed by the strength of the chain. Acceptable chain speed and ultimate strength are far less than that of conveyor belting.
Additionally, the prior art bulk material conveyor apparatus arrangements typically have bulk material quantity rate of material-movement limitations as related to movement-power inputs, and also frequently have endless belt speed and length limitations relating to movement-power inputs. Such limitations are keyed to the internal friction and angle of repose factors of the particular bulk material being conveyed.
I have discovered an improved en masse bulk material conveyor apparatus construction which in substantial degree overcomes the limitations associated with the prior art conveyor apparatus. The improved bulk material conveyor apparatus of the present invention, in addition to being capable of moving larger quantities of a particular bulk material with reduced input movement-power, permits bulk material conveyor apparatus installations of greater lengths and with greater material-moving belt speeds.
Other objects and advantages of the present invention will become apparent from a consideration of the descriptions, drawings, and claims which follow.